Adjusting sewing machine stitches uses three controls — stitch length, stitch width, and tension — so start by testing on scrap fabric.
When fabric comes out with loops, tangles, or puckers, most sewists grab the tension dial first — usually the wrong move. Adjusting stitches means understanding three separate controls: stitch length, stitch width, and upper-thread tension. Each changes the stitch predictably; the golden rule is to change one setting at a time and sew a test line on scrap fabric before touching your project.
The Three Stitch Controls: Which One Does What
Every household machine uses the same three controls. Stitch length decides how far the needle travels between stitches; stitch width decides how wide a zigzag or decorative stitch swings; upper-thread tension decides how firmly top and bobbin threads lock together in the fabric.
- Stitch length: a higher number makes longer stitches, a lower number pulls them closer together.
- Stitch width: widens or narrows zigzag and decorative stitches. Straight stitches sew with width at zero or none applied.
- Upper-thread tension: lowering the dial loosens the upper thread; raising it tightens the pull. Change tension last, after rethreading, checking the needle, and retesting.
Brother machines follow the same pattern: length and width buttons adjust each control. On mechanical models, a length dial does the same job and a pattern or width dial handles zigzag width. Computerized machines often set optimal length and width for your chosen pattern but allow manual adjustment.
How Do You Change Stitch Length And Width?
Change length and width with the labeled buttons or dials — the correct starting number is in your manual’s stitch chart, and the procedure is identical for dial and button machines. First choose the stitch pattern, then set length, then adjust width if the stitch uses one.
- Raise the needle to its highest position so fabric moves freely.
- Select the stitch pattern. A straight stitch has no width; zigzag and decorative stitches do.
- Set stitch length with the length buttons or dial. Test with a longer setting if thread is bunching.
- Set stitch width for zigzag patterns.
- Sew a test line on scrap. Success looks like even, flat stitches with no loops and a clean zigzag spread.
Avoid changing the dial while the needle is in the fabric on models that warn against it. Brother also cautions: after a width change, slowly turn the handwheel toward you and confirm the needle clears the presser foot before sewing.
Why Do Stitches Bunch Or Look Uneven?
Bunched threads and uneven stitching usually trace back to stitch length and tension, in that order — lengthen the stitch first, retest, and adjust tension only if the problem remains. Continuing to sew with bunched stitches risks more than ugly seams: Brother warns it can bend or break the needle.
| Stitch Problem | Control To Change | Which Way To Move It |
|---|---|---|
| Loops on the underside of the fabric | Upper-thread tension | Tighten by raising the tension dial a small step |
| Fabric puckers or bobbin thread shows on top | Upper-thread tension | Loosen by lowering the tension dial |
| Thread bunches and tangles | Stitch length | Increase the stitch length |
| Stitches sit too far apart | Stitch length | Decrease the length number |
| Zigzag spread too narrow | Stitch width | Increase the width |
| Zigzag spread too wide | Stitch width | Decrease the width |
| Needle close to presser foot after width change | Handwheel check | Turn handwheel by hand to confirm clearance |
Before touching tension, rethread completely and swap in a fresh needle — threading errors cause most tension-like symptoms. If fabric still feeds unevenly, lengthen the stitch and retest. For a machine that handles stitch settings mostly on its own, see our tested picks for the best automatic stitching machine options.
The Fix Order That Works
When a stitch comes out wrong: rethread, change the needle, adjust length, adjust width, then fine-tune tension — retesting after every change. Bunched stitches call for a longer length; loops or puckers call for tension changes a step at a time. For persistent bunched or gappy patterns, Brother’s procedure opens a hidden adjustment display — power off, hold the key your manual specifies while powering on, adjust with the stitch length keys, and resew. Press “+” if bunched; press “-” if gappy.
FAQs
Should I adjust tension before checking the stitch length?
No. Tension is the finickiest control — touch it last after rethreading, changing the needle, and adjusting length and width. Most uneven stitching starts with wrong length or threading, not tension. Test on scrap after each change, and move tension only in small steps once other controls are ruled out.
What stitch length and width should I start with?
Start with the numbers in your machine’s manual for your fabric and stitch — they are the manufacturer’s tested baseline. For medium-weight woven fabric, a straight stitch around 2 to 2.5 on dials marked in millimeters is reasonable. Zigzag width depends on the fabric edge and desired density.
Can I sew zigzag stitches with a twin needle?
Only with caution. Turn the handwheel by hand to confirm needle clearance before sewing, since a wide zigzag with a twin needle risks a bent or broken needle.
References & Sources
- Brother. “Sewing Guide.” Official manual covering stitch length and width controls and the warning about bunched stitches breaking needles.
- Janome. “Instruction Book.” Explains stitch length and width dials and how the tension dial loosens or tightens upper-thread tension.
- Brother Support. “FAQ — Stitch Adjustment.” Details the power-on stitch-tuning procedure and twin-needle width limits.
